Configuration of a Belt Attachment Part

ABSTRACT

A flat belt attachment includes a first bar that connects corresponding positions of a pair of base bars facing each other; and a second bar that is parallel to the first bar and connects the base bars. The second bar includes a second inclined portion at an end portion, and the second inclined portion is shaped to approach the first bar toward a proximal end of the second inclined portion.

TECHNICAL FIELD

The present invention relates to a structure of a belt attachment.

BACKGROUND ART

There has been typically known a connectable and separable buckle that is attached with a belt and is adapted to connect and separate a plurality ends of the belt.

Some of buckles are provided with a belt attachment to which a belt is attached, the belt attachment having at least two bars.

For instance, Patent Literature 1 discloses a belt adjuster of a buckle, in which the belt adjuster includes a fixing rod, a folding rod including a convex portion and a concave portion, and a locking rod including a concave portion and a convex portion in a manner to face the folding rod.

Patent Literature 2 discloses a buckle including a first bar having a serration and a second bar having a cross section of an axisymmetric triangle about a third corner (i.e., a center line) of the second bar and having a serration at an apex part of the triangle in order to gain friction resistance against a belt.

CITATION LIST Patent Literature(s)

-   Patent Literature 1 Japanese Patent No. 2773789 -   Patent Literature 2 Japanese Patent No. 3156105

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

An interval between the folding rod and the locking rod in Patent Literature 1 and an interval between the first bar and the second bar in Patent Literature 2 are made slightly smaller than an interval from other rods or bars. With this arrangement, an engagement angle between the belt and each corner is made small, so that friction resistance between the belt and each corner is increased to improve an engagement strength. In such a structure, when the belt is inserted between the rods or bars, operation may be complicated due to such a narrow interval.

Moreover, in the belt adjuster of the buckle disclosed in Patent Literature 1, since the convex and concave portions need to be provided to each of the folding and locking rods, a structure may be complicated and a manufacturing process may also be complicated. Also in the buckle disclosed in Patent Literature 2, since the first and second bars have a serration, a structure may be complicated and a manufacturing process may also be complicated.

Further, the buckle disclosed in Patent Literature 2 uses the second bar having a cross section of a triangle having a center line at the third corner of the second bar. However, it may impose a restriction in manufacturing to form the second bar having such an axisymmetrically triangular cross section, so that manufacturing of the buckle may not be easy.

Accordingly, an object of the invention is to provide a simply structured belt attachment into which a belt can be easily inserted.

Means for Solving the Problems

According to an aspect of the invention, a flat belt attachment includes a first bar that connects corresponding positions of a pair of base bars facing each other; and a second bar that is parallel to the first bar and connects the base bars, in which the second bar includes a second inclined portion at an end portion, and the second inclined portion is shaped to approach the first bar toward a proximal end of the second inclined portion.

In the above aspect of the invention, the inclined portions are provided to the end portions of each of the first and second bars. Accordingly, when tension is applied on the belt, the end portions of one of the bars guide the belt to be pressed onto the other of the bars.

With this operation, the belt is brought into pressure-contact with the first bar or the second bar by tension. Accordingly, even when the interval between the first bar and the second bar is not reduced, a sufficient friction resistance between the belt and each of the bars is obtainable. Consequently, the belt attachment according to the above aspect of the invention can facilitate insertion of the belt while providing a sufficient friction resistance between the belt and each of the bars.

Moreover, since a sufficient friction resistance between the belt and each of the bars is obtainable, neither of the bars requires convex/concave portions or serrations, so that a structure of the belt attachment is simplified and manufacturing thereof becomes easy.

In the above aspect of the invention, it is desirable that the second bar has a linear middle portion.

With this arrangement, since the middle portion of the second bar is linear, the belt can be easily inserted between the first bar and the second bar.

In the above aspect of the invention, it is desirable that the first bar includes a first inclined portion at an end portion in the same direction and shape as those in the second bar.

With this arrangement, since the first bar has the first inclined portion at each of the end portions in the same direction and shape as in the second bar, the interval between the first bar and the second bar at the end portion is not narrowed and can be kept at the same interval as the interval between the middle portions of the first bar and the second bar. Accordingly, the belt can be easily inserted between the first bar and the second bar.

In the above aspect of the invention, it is desirable that the first bar and the second bar each are axisymmetric around the center in a thickness direction.

With this arrangement, since the first bar and the second bar each are axisymmetric around the center in the thick direction, friction resistance between the belt and each of the first bar and the second bar becomes axisymmetric in the width direction of the belt. Accordingly, a stable belt attachment performance is achievable.

In the above aspect of the invention, it is desirable that the second bar has a cross section enlarging toward the first bar.

With this arrangement, since the cross section of the second bar enlarges toward the first bar, the belt applied with tension significantly bulges toward the first bar by a restoring force.

Accordingly, when the belt is applied with tension, the interval between the first bar and the second bar becomes smaller than an actual interval in a pseudo manner.

Consequently, in the above aspect of the invention, when the belt is inserted between the first bar and the second bar, the belt can be easily inserted into a wide interval. When the belt is inserted and applied with tension, since the interval becomes smaller than the actual interval in a pseudo manner, a sufficient friction resistance between the belt and each of the bars can be ensured.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view showing an overall structure according to an exemplary embodiment of the invention.

FIG. 2 is a plan view showing a plug according to the above exemplary embodiment.

FIG. 3 is an enlarged front view showing that no tension is applied on a belt inserted into a belt attachment in the above exemplary embodiment.

FIG. 4 is an enlarged front view showing that tension is applied on the belt inserted into the belt attachment in the above exemplary embodiment.

FIG. 5 is an enlarged cross section of the belt attachment according to the above exemplary embodiment.

FIG. 6 is an enlarged cross section showing that the belt is inserted into the belt attachment in the above exemplary embodiment.

FIG. 7 is a plan view showing an overall structure according to a modification of the invention.

DESCRIPTION OF EMBODIMENT(S)

An exemplary embodiment of the invention will be described below with reference to the attached drawings.

FIGS. 1 to 6 show an exemplary embodiment of the invention.

An overall structure of a front release buckle will be described below with reference to FIG. 1.

FIG. 1 is a plan view showing the overall structure according to the exemplary embodiment of the invention.

As shown in FIG. 1, a front release buckle 1 according to this exemplary embodiment includes a plug 10 and a socket 20 into which the plug 10 is inserted for engagement.

The front release buckle 1 is used to couple and separate ends of a belt B. The front release buckle 1 includes the plug 10 integrally formed of a synthetic resin and the socket 20 also integrally formed of a synthetic resin.

The plug 10 and the socket 20 may be formed of other materials such as metal instead of a synthetic resin according to other molding methods (e.g., rapid manufacturing and casting) instead of an injection molding.

A structure of a plug will be described below with reference to FIG. 2.

FIG. 2 is a plan view of the plug according to the above exemplary embodiment.

In FIG. 2, an entirety of the plug 10 is integrally formed of a synthetic resin by injection molding. The plug 10 includes a base 11 having a pair of legs 12, an engaging portion 14 formed in each of the legs 12, and a belt attachment 19 into which a belt or the like is inserted.

The legs 12 extend in parallel to each other in a length direction of the base 11 (an insertion direction of the plug 10 to the socket 20, i.e., in a vertical direction in FIG. 1) from both sides of the base 11 in a width direction (a direction orthogonal to the insertion direction of the plug 10 to the socket 20 and a thickness of the socket 20, i.e., a horizontal direction in FIG. 1). A portion from the middle to the tip end of each of the legs 12 is elastically deformable in a thickness direction (i.e., a direction orthogonal to the width direction and the insertion direction described above).

The pair of legs 12 are gradually inclined in the thickness direction in a manner to approach each other as the legs 12 extend toward the respective tip ends of the legs in the insertion direction, so that an entirety of the legs 12 can receive a force for elastic deformation in the thickness direction.

The engaging portion 14 is formed as a projection extending from the tip end of each of the legs 12 in the width direction. The tip end of each of the legs 12 is T-shaped in a plan view. The engaging portion 14 formed at the tip end of each of the legs 12 is formed to have a thickness (i.e., height) that does not exceed a height of each of the legs 12.

The engaging portion 14 includes an inclined portion 14B that is formed at the tip end of each of the legs 12, and a connecting inclined portion 14D that connects the inclined portions 14B in the width direction. With this connecting inclined portion 14D, the pair of legs 12 are restricted from being deformed in the width direction by an external force. Further, when the pair of legs 12 are elastically deformed in the thickness direction, this connecting inclined portion 14D allows the pair of legs 12 to be deformed by the same volume.

The inclined portion 14B includes an inclined surface 14A that is gradually inclined so that the thickness of the engaging portion 14 becomes smaller toward the tip end of each of the legs 12 in the insertion direction. The connecting inclined portion 14D includes a connecting inclined surface 14C.

A pair of holders 16 are provided at outer sides of the pair of legs 12. The pair of holders 16 are rod-like members that are disposed on the base 11 apart from each other in the width direction of the base 11 and extend in the insertion direction. A tip end of each of pair of holders 16 is spaced apart from the engaging portion 14. A thickness of each of the holders 16 is formed to be smaller than the thickness of the base 11 and larger than thickness of each of the legs. 12.

Each of the holders 16 includes a projecting holder 16A that is provided along an outer width direction of the each of the holders 16.

The engaging portion 14 and the holders 16 are guided by undulations (not shown) formed on an inner side of the socket 20 so that the plug 10 is guided to an appropriate position in an insertion operation.

The belt attachment 19 is formed in a middle area of the base 11. The belt attachment 19 includes: a belt attachment hole 19A that is provided in the middle of the inside of the belt attachment 19 and into which an end of the belt is inserted; a first bar 19B that extends in the width direction of the plug 10 between a pair of base bars 11A between the ends of the plug 10 (i.e., the ends of the bars 11A); and a second bar 19C that is formed in the middle of the belt attachment hole 19A in a manner to bridge over the belt attachment hole 19A. The second bar 19C divides the belt attachment hole 19A into an insertion-direction front hole 19D and an insertion-direction rear hole 19E.

With this arrangement, a belt (not shown) is inserted into the belt attachment hole 19A and wound around the second bar 19C to be contacted with the first bar 19B. Thus, the belt can be engaged and fixed to the plug while a length of the belt can be adjusted.

The belt attachment 19 is formed to be axisymmetric relative to the insertion direction.

The second bar 19C has a linear middle portion and a second inclined portion 19C1 at end portions, the second inclined portion 19C1 being shaped to approach the first bar 19B toward a proximal end of the second bar 19C. The first bar 19B has a linear middle portion and a first inclined portion 19B1 at end portions, the first inclined portion 19B1 being shaped to separate from the second bar 19C toward a proximal end of the first bar 19B.

The first inclined portion 19B1 and the second inclined portion 19C1 have an inclined shape corresponding to each other. An interval N1 between the middle portions of the first bar 19B and the second bar 19C is equal to an interval N1 between the end portions thereof. An interval in the insertion direction between the proximal end of the second bar 19C and the middle portion of the first bar 19B is defined as an interval N2.

A belt being attached to the belt attachment will be described with reference to FIGS. 3 and 4.

FIG. 3 is an enlarged front view showing that no tension is applied on the belt inserted into a belt attachment in the above exemplary embodiment. FIG. 4 is an enlarged front view showing that tension is applied on the belt inserted into a belt attachment in the above exemplary embodiment.

As shown in FIG. 3, no tension is applied on the belt B inserted in the insertion-direction rear hole 19E. At this time, in a cross section, the belt B sags with ends lying along the second inclined portion 19C1.

On the other hand, as shown in FIG. 4, no tension is applied on the belt B inserted in the insertion-direction rear hole 19E. At this time, since a force toward the first bar 19B is applied on the belt B, a cross-sectional middle portion of the belt B becomes linear to be contacted with a lateral side of the middle portion of the first bar 19B. Moreover, since the cross-sectional ends of the belt B are guided toward the first bar 19B by the second inclined portion 19C1 at the end portions of the second bar 19C, the ends of the belt do not lie along the shape of the second inclined portion 19C1, so that a cross section of the belt B becomes linear.

A cross section of the belt attachment will be described below with reference to FIG. 5.

FIG. 5 is an enlarged cross section of the belt attachment according to the above exemplary embodiment.

As shown in FIG. 5, the cross section of the second bar 19C is formed in a shape enlarging toward the first bar 19B.

The second bar 19C has a substantially trapezoidal cross section having apex corners C1 facing the first bar 19B and apex corners C2 positioned opposite to the apex corner C1. A cross section of the first bar 19B has apex corners C3 facing the second bar 19C.

In the substantially trapezoidal cross section of the second bar 19C, the apex corners C1 facing the first bar 19B are positioned inside the two apex corners C3 of the first bar 19B facing the second bar 19C within a thickness of the belt attachment 19.

The belt being inserted in the belt attachment will be described with reference to FIG. 6.

FIG. 6 is an enlarged cross section showing that the belt is inserted in the belt attachment in the above exemplary embodiment.

FIG. 6 shows the belt B1 on which no tension is applied and a belt B2 on which tension is applied.

The belt B1 (B2) is inserted into the insertion-direction front hole 19D, contacted with the two apex corners C2 and one of the apex corners C1, inserted into the insertion-direction rear hole 19E, contacted with one of the apex corners C3, and pulled out of the belt attachment 19.

In this arrangement, a path of the belt B1 is different from a path of the belt B2 in the insertion-direction rear hole 19E. Specifically, since no tension is applied on the belt B1, the belt B1 is arranged in a gentle (i.e., not peaked) circular path passing the three apex corners C1 and C2, and then reaches the apex corner C3. Accordingly, since a restoring force of the belt B is dispersed at the three apex corners C1 and C2 where the belt B passes, a large restoring force is not generated on the belt B located between the apex corners C1 and C3. Accordingly, the path of the belt B1 becomes linear in the insertion-direction rear hole 19E.

On the other hand, since tension is applied on the belt B2, the path of the belt B2 conforms with the cross section of the second bar 19C between the three apex corners C1 and C2, and then reaches the apex corner C3. Accordingly, since a restoring force of the belt B is not dispersed at the three apex corners C1 and C2 where the belt B passes, a large restoring force is generated on the belt B located between the apex corners C1 and C3. Accordingly, the belt B2 significantly bulges toward the first bar 19B near the apex corner C1, and then reaches the apex corner C3 in a linear path.

In the above exemplary embodiment, the following advantages are attainable.

In the exemplary embodiment, the inclined portions 19B1 and 19C1 are respectively provided to the end portions of the first and second bars 19B and 19C. Accordingly, when tension is applied on the belt B, the second bar 19C guides the belt B so as to be pressed onto the first bar 19B. With this operation, the belt B is brought into pressure-contact with the first bar 19B by tension.

Accordingly, without decreasing the interval between the first bar 19B and the second bar 19C, a sufficient friction resistance between the belt B and each of the bars 19B and 19C is obtainable.

Consequently, in the belt attachment 19 according to the exemplary embodiment, the belt B can be easily inserted into the insertion-direction rear hole 19E and a sufficient friction resistance between the belt B and each of the bars 19B and 19C is obtainable.

Moreover, since a sufficient friction resistance between the belt B and each of the bars 19B and 19C is obtainable, neither of the bars 19B and 19C requires convex/concave portions or serrations, so that a structure of each of the bars 19B and 19C is simplified and manufacturing of the bars 19B and 19C becomes easy.

In the exemplary embodiment, since the middle portion of the second bar 19C is linear, the belt B having a flat cross section can be easily inserted between the first bar 19B and the second bar 19C.

In the exemplary embodiment, since the first bar 19B has the first inclined portions 19B1 at the end portions in the same direction and shape as in the second bar 19C, the interval between the first bar 19B and the second bar 19C at the end portions is not narrowed but can be kept at the same interval as the interval N1 between the first bar 19B and the second bar 19C at the middle portions. Accordingly, the belt B can be easily inserted between the first bar 19B and the second bar 19C.

In the exemplary embodiment, the first bar 19B and the second bar 19C each are axisymmetric around the center in the thick direction. Accordingly, an amount of the friction resistance between the belt B and each of the first bar 19B and the second bar 19C becomes axisymmetric in the width direction of the belt B. Accordingly, a stable belt attachment performance is achievable.

In the exemplary embodiment, since the second bar 19C has a substantially trapezoidal cross section enlarging toward the first bar 19B, the path of the belt B2 on which tension is applied conforms with the cross-sectional shape of the second bar 19C passing the three apex corners C1 and C2, and then reaches the apex corner C3. Accordingly, since a restoring force of the belt B is not dispersed at the three apex corners C1 and C2 where the belt B passes, a large restoring force is generated on the belt B located between the apex corners C1 and C3. Consequently, the belt B2 significantly bulges toward the first bar 19B near the apex corner C1, and then reaches the apex corner C3 in a linear path.

Thus, when tension is applied, the interval between the first bar 19B and the second bar 19C becomes smaller than the interval N1 in a pseudo manner. Consequently, in the exemplary embodiment, when the belt B is inserted into the insertion-direction front hole 19D and the insertion-direction rear hole 19E, the belt B is easily inserted since the interval N1 is wide. When tension is applied on the belt B after insertion, since the interval between the first bar 19B and the second bar 19C becomes smaller than the interval N1 in a pseudo manner, a sufficient friction resistance between the belt attachment 19 and the belt can be ensured.

Modifications

It should be noted that the invention is not limited to the above arrangements of the exemplary embodiments but encompasses the following modifications.

In the exemplary embodiment, the belt attachment 19 is used in the front release buckle 1. However, for instance, the belt attachment 19 may be employed as a belt-length-adjusting belt attachment (commonly called an “adjuster”), and further, may be employed in a side release buckle, a pouch clip and the like.

In the exemplary embodiment, the first bar 19B has the first inclined portion 19B1. However, a structure of the first bar 19B is not limited to this. The first bar 19B may be formed without the first inclined portion.

Although the shape of the first inclined portion 19B1 matches with the shape of the second inclined portion 19C1, the shape of the first inclined portion 19B1 may be different from the shape of the second inclined portion 19C1.

INDUSTRIAL APPLICABILITY

The invention is a buckle for connecting belts and usable as a front release buckle, a side release buckle, an adjuster, a pouch clip and the like.

EXPLANATION OF CODES

-   11A: base bar -   19: belt attachment -   19A: belt attachment hole -   19B: first bar -   19B1: first inclined portion -   19C: second bar -   19C1: second inclined portion -   B: belt 

1. A flat belt attachment comprising: a first bar that connects corresponding positions of a pair of base bars facing each other; and a second bar that is parallel to the first bar and connects the base bars, wherein the second bar comprises a second inclined portion at an end portion, and the second inclined portion is shaped to approach the first bar as extending toward a proximal end of the second inclined portion.
 2. The belt attachment according to claim 1, wherein the second bar has a linear middle portion.
 3. The belt attachment according to claim 1, wherein the first bar comprises a first inclined portion at an end portion in the same direction and shape as those in the second bar.
 4. The belt attachment according to claim 1, wherein the first bar and the second bar each are axisymmetric around the center in a thickness direction.
 5. The belt attachment according to claim 1, wherein the second bar has a cross section shaped to enlarge toward the first bar. 